Abstract
OBJECTIVE: To evaluate the effect of the L-PRF plug on the rate of maxillary canine retraction during the comprehensive orthodontic treatment. MATERIALS AND METHODS: The present split-mouth randomized controlled trial included 15 female patients (age range, 18-25 yrs) requiring all 1st premolars extraction for correction of their malocclusion. Right and left sides of the maxillary arch in each patient were randomly allocated to control and experimental sides. Simultaneous canine retraction was initiated immediately after the extraction of 1st premolars on the control side, and placement of L-PRF plugs on the experimental side 1st premolar extraction socket. The amount of canine retraction was evaluated from 3D models of the maxillary study models prepared immediately before (T(0)), then at 1 week (T(1)), 2 weeks (T(2)), 4 weeks (T(3)), and 8 weeks (T(4)) after the extraction of first premolars and placement of L-PRF. The concentration of IL-6 in the GCF was estimated at T(0), T(1), T(2), T(3), and T(4). RESULTS: Of 15 enrolled, one participant lost during the follow-up. The data of fourteen maxillary arches (14 experimental and 14 control sides) were analyzed. During the first four weeks of observation, the experimental sides had more canine retraction of 0.25 mm (P = 0.001). The mean concentrations of IL-6 at mesial and distal aspects of experimental and control side canines were comparable (P > 0.05). There was a significant increase in IL-6 concentration in the distal compared to the mesial aspects of canine in experimental sides at T(1) (P = 0.004) and T(2) (P = 0.030). There was no correlation between the IL-6 levels and the amount of canine retraction. No adverse effects to any patient were observed during the eight weeks study period. CONCLUSION: Although the application of L-PRF accelerated the maxillary canine retraction by 0.32 mm throughout the eight weeks, with most of the acceleration occurring in the first four weeks, but it was not clinically significant in decreasing the total duration of orthodontic treatment.